Project preview: Comments/suggestions/testing welcome

My save state was in the moogle explanation so that I wouldn't have to watch the cutscene over and over. I made the state after the first time the fight locked, so it's not a matter that the save state locked the fight. I did make the walk again from the save and that one vomammoth still causes a lock.

I do believe the green brawlers being conscripts or privates to be likely, though their appearance being strictly in South Figaro's occupation is bizarre. In my own hack, I did a palette swap so that the Brown soldiers were scrappy and Locke would steal one of their uniforms, since the bulk of Gestahl's army is comprised of forced conscription of conquered regions (Tzen, Albrook, Maranda). I also color-coded the soldiers by general, though (Green for Leo, Red for Kefka, Blue for Celes) so it was a little more involved than a quick palette swap.

I'll give your update a try.

EDIT: Ran through it again, the soft lock is gone now (And you fixed Gestahl!)! Without the pressure to evade that freeze I was able to handle the fight with a turtle strategy, which is how I usually prefer to deal with these events. It's definitely harder than Vanilla but not too difficult; I forked the parties to block the three routes, fought until it looked like the field was empty, and then ran to Marshal with Mog's party. While players may not be able to grind right before the fight, they can still gain levels with Terra in the cave behind Arvis's house. If you're worried about resources, you could add tonics to the wrenchers' drop table in there... it'll help with the early game without having a huge impact later as tonics basically stink past level 6.
I'm the wrong person to ask about variable routing, though, because I never pay enough attention to the NPCs to tell if they're taking a different path. I think you'll want a speedrunner to try this too, to see how they react to it.
If you're still worried about not having a shop before the fight, and if you're feeling extra ambitious, you could rework the moogle cave behind the battleground to a heal-and-shop prep area before the actual tower defense; block Locke in with invisible NPCs and make the actual start of the Marshal attack triggered by talking to the swooned Terra. I don't think that's necessary in this case, but it is an option if you're still concerned.

Very nice additions so far.

EDIT EDIT:
I don't know if you ever saw this thread before, but m06 expanded on the code you did to extend NPC sprites. You might get some ideas for menu fixes from that code. If it works, saves some work, right?
https://www.ff6hacking.com/forums/thread-3580.html